Trunked radio frequency (RF) systems are normally constructed with enough infrastructure (e.g. antenna sites, repeaters, etc.) to match the usage rate per square mile of coverage (typically measured in Erlangs load per square mile). In a typical trunked radio system, the radio frequency channels are shared by a multitude of radio unit users over the geographic area serviced by the particular transmitter site in question.
In order to provide radio service over a large geographic service area, as is typically required in public safety and private utility radio systems, additional fixed radio transmitter sites are constructed and linked together with a trunked network such as a Coverage Plus.TM. or SMARTNET.TM. system manufactured by Motorola, Inc. Once again, the number of channels (repeaters) required at each site depends on the actual traffic load in terms of Erlangs. Many times when designing a trunked radio system, certain sites are found to have low levels of usage by radio users, these are typically sites located away from the central system areas (typically away from congested urban areas). Unfortunately, even though these sites have very limited traffic (usually under 100 radios), the area still requires at least one voice channel. Since it is desired to make these low traffic density sites part of the overall trunking system and since for each remote site a dedicated control channel is also required do to the system design requirements found in dedicated control channel trunking systems (systems such as the Coverage Plus.TM., SMARTNET.TM. and other dedicated control channel trunked systems), it becomes very expensive to support these remote sites, since at the minimum two repeaters are required at a site. A need exists for increasing the capabilities of single repeater sites which are part of a larger trunked system having dedicated control channel sites.